1)To have your manly meat spear fail at the precise moment it is needed.

2)To not be soft, but not hard enough for sexual intercourse.

3)To lose faith, and to not lose your virginity.

This is a pun on the phrase "rolled on impact"
Brian: Yeah, I would have totally pounded her last night, but I went flaccid on impact.
by klaus__ August 23, 2008
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